README
Census 2000 Summary File 2 Delivered via FTP
Contents
About the FTP Application
Other Sources of the Data
File Naming Convention
Technical Documentation
Data Records and Segmentation
File Record Layout
FTP File Transfer
UnZipping the Files
Spreadsheet and Data Base Aids
Maximum File Sizes
¦ For step-by-step instructions for moving the data and the structure into a spreadsheet (including
screen shots), please see www.census.gov/support/SF2ASCII.html .
¦ Structure files in Access97 and other formats are available at
http://www.census.gov/support/2000/SF2/ .
¦ We are unable to provide one-on-one support for applications of the data to specific
spreadsheets or data base software.
About the FTP Application
¦ The application is intended for experienced users of census data, compressed files, and
spreadsheet/database software.
¦ FTP users should have a fast file transfer capability.
¦ Users of the FTP application need to unzip the compressed file after downloading, then import it
into the spreadsheet/database software of their choice for data analysis and table presentation.
Other Sources of the Data
¦ American FactFinder at factfinder.census.gov .
¦ This system provides Internet access to all tables plus additional derived tables called Quick
Tables and Geographic Comparison Tables.
¦ The system can create thematic maps on various data items.
¦ The system can create reference maps defining the geographic area.
¦ Tables are available on American FactFinder on the morning of public release.
¦ DVD/CD-ROM
¦ CD-ROMs with software are available for individual states on or shortly after the public
release date.
¦ DVDs are created after all states are released.
¦ They can be purchased online ($50 for CD-ROM; $70 for DVD) from the Census Catalog
(www.census.gov, select Census Catalog from left sidebar) or ordered by telephone from the
Customer Services Center (301-457-INFO.
¦ DVDs and CD-ROMs contain the same software.
¦ Software is proprietary but are in a format the can easily be imported into data bases or
spreadsheets.
¦ CD-ROMs with software are available for individual states on or shortly after the public
release date.
File Naming Conventions
¦ The naming convention for geographic header files is ssgeo_uf2.zip
¦ ss is USPS state abbreviation
¦ The codes are in technical documentation on page 7-1, located at
http://www.census.gov/prod/cen2000/doc/sf2.pdf
¦ geo_uf2.zip is a constant across SF2 geographic header names.
¦ Naming convention for SF2 data files is ssiiiyy_uf2.zip.
¦ ss is USPS state abbreviation
¦ iii is the characteristic iteration (total population, race groups, American Indian and Alaska
Native tribes, and Hispanic/Latino groups)
¦ Characteristic iteration codes are in the Appendix H of the technical documentation,
which is available at http://www.census.gov/prod/cen2000/docs/sf2.pdf - page=278.
¦ yy is the number of the file
¦ Valid codes are 01 through 04. See below for distribution of tables across files.
¦ _uf2.zip is a constant across SF2 data file names
Technical Documentation
¦ The complete technical documentation for SF2 is available at
http://www.census.gov/prod/cen2000/doc/sf2.pdf .
Data Records and Segmentation
¦ If the total population (iteration 001) for a geographic entity is less than 100, there will be no
geographic header record and no data records for that area.
¦ Example: The population of One Road township, Roberts County, South Dakota is 54. There will
be no records, either geographic header or data, for this area.
¦ If the population for a race, tribe, or Hispanic/Latino group (iterations 002-463) within a
geographic entity is 100 or greater, geographic header and data records will be present for the
group.
¦ Example: The Black or African American alone population for Bremer County, Iowa is 110. There
will be a geographic header record and data records for the Black/African American iteration
(iteration 004) for this area.
¦ If the population for a race, tribe, or Hispanic/Latino group (iterations 002-463) within a
geographic entity is less than 100, geographic header and data records will not be present
for that group.
¦ Example: The Hispanic/Latino population for South Harding CCD, Harding County,
New Mexico is 19. There will be no data records for the Hispanic/Latino iteration
(iteration 400) for this area.
¦ Table distribution across data files is as follows:
File name Number Starting Ending
of data matrix matrix
items number number
ssiii01_uf2 219 PCT1 PCT4
ssiii02_uf2 236 PCT5 PCT19
ssiii03_uf2 174 PCT20 PCT36
ssiii04_uf2 137 HCT1 HCT11
¦ Five fields are carried over from the geographic header file into each data file.
¦ These fields are file identification (FILEID), state abbreviation (STUSAB),
characteristic iteration (CHARITER), characteristic iteration file sequence number
(CIFSN) and logical record number (LOGRECNO).
¦ These five fields appear in the geographic header record are in a fixed field format.
¦ These five fields appear in the four data files in a comma delimited format.
¦ These fields are used to "match" records in the four data files for a particular
characteristic iteration to the geographic information in the geoheader.
¦ A file set structure schematic appears in the technical documentation (page 2-4) which is
located at http://www.census.gov/prod/cen2000/doc/sf2.pdf
File Record Layout
¦ For a layout of the individual tables for each file, see the technical documentation at
www.census.gov/prod/cen2000/doc/sf2.pdf . Select Chapter 6, Summary Table Outlines.
FTP File Transfer
¦ Summary File 2 (SF2) FTP directory is at ftp2.census.gov/census_2000/datasets/Summary_File_2 .
¦ Each state directory provides all files available for the identified state.
¦ The directory for each state has a geographic header file and four files for each iteration
(total population, race, tribe, or Hispanic/Latino group) having a population of 100 or
more.
¦ There is a potential (but not likely) for 1,000 files for each state—one geographic header
file and four data for each of the 250 iterations. This occurs only when each of the 250
groups has a population of 100 or more.
¦ The chart on page 3 of this document lists the table numbers available in each of the four
files.
¦ Once uncompressed, the files are in a flat ASCII format.
¦ No software is provided.
¦ Downloading multiple files
¦ UNIX environment—"mget" subcommand allows transfer of multiple files using the
wildcard character.
¦ Example: ftp> prompt off
ftp>mget ne* (for this example, Nebraska is selected).
¦ Windows Environment—many FTP products have been developed which have the
capability to download multiple files with a single command.
¦ We used the ws_ftp product in testing the download.
¦ A demonstration copy is available at http://www.ipswitch.com/ .
¦ An Internet search using the term "download multiple files" yielded other similar
products.
¦ For step-by-step instructions with screen shots, please see
http://www.census.gov/support/2000/SF2/ ..
Unzipping the Files
¦ Files compress at approximately 95% compression.
¦ Any standard UnZIP software package can be used.
¦ In testing we used PKZIP for Windows. It's available at www.pkware.com. .
¦ Unzipped file is in flat ASCII format.
¦ For step-by-step instructions with screen shots, please see
http://www.census.gov/support/2000/SF2/ .
Unzipped Files
¦ Geographic header file has fixed fields.
¦ File data dictionary is at http://www.census.gov/prod/cen2000/doc/sf2.pdf . See chapter 7 for the
data dictionary.
¦ Data files (files 01-04) have comma delimited fields
¦ Fields from the geographic header file carried over to the data files are comma
delimited in the data files .
Spreadsheet and Data Base Aids
¦ For step-by-step instructions with screen shots for moving the data and structure to a spreadsheet,
please see www.census.gov/support/SF2ASCII.html .
¦ Structure files in Access97 and other formats are available at
http://www.census.gov/support/2000/SF2/ .
¦ We are unable to provide one-on-one support for applications of the data to specific
spreadsheets or data base software.
Maximum File Sizes
¦ The figures below are the maximum file sizes for SF2 and are identical to the sizes for SF1.
¦ Size of state files will vary considerably from these figures, depending on the number of total
population, race, tribe, or Hispanic/Latino groups within the state having a population of 100 or
over.
¦ As state tables are run, we will update this listing.
SF2
GeoHeader and File01-File04
Maximum File Sizes
unzipped zipped
State
Alabama 1.7G 87M
Alaska .3G 11.7M
Arizona 1.5G 51M
Arkansas 1.5G 35M
California 5.1G 260M
Colorado 1.5G 75M
Connecticut .6G 28M
Delaware .2G 7.8M
District of
Columbia .6G 4.6M
Florida 3.4G 170M
Georgia 2.3G 110M
Hawaii .2G 27.8M
Idaho .9G 12.5M
Illinois 4.1G 209M
Indiana 2.1G 108M
Iowa 1.7G 37M
Kansas 1.7G 88M
Kentucky 1.1G 58M
Louisiana 1.5G 77M
Maine .5G 10M
Maryland .9G 54M
Massachusetts 1.2G 58M
Michigan 2.7G 136M
Minnesota 2G 105M
Mississippi 1.4G 33.5M
Missouri 2.5G 125M
Montana .9G 12M
Nebraska 1.4G 21M
Nevada .7G 23M
New
Hampshire .3G 8M
New Jersey 1.7G 82M
New Mexico 1.4G 26M
New York 3.6G 180M
North Carolina 2.5G 123M
North Dakota .9G 8M
Ohio 2.8G 138M
Oklahoma 1.8G 90M
Oregon 1.4G 71M
Pennsylvania 3.5G 174M
Rhode Island .24G 12M
South Carolina 1.5G 35M
South Dakota .8G 12M
Tennessee 1.9G 42M
Texas 6.8G 198M
Utah .8G 21M
Vermont .25G 8M
Virginia 1.5G 64M
Washington 2G 100M
West Virginia .9G 18M
Wisconsin 2G 100M
Wyoming 7G 6M
Puerto Rico .8G 35M
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